Gorgom now wants to know the secret behind the strength of Kotaro Minami and since this task is quite impossible, they decided to go with the next best thing, to use athletes to study Kotaro. This is when Professor Kuromatsu's laboratory comes in as he begins his experiments on humans.

If there is one thing that bothered me in Gorgom's latest plot is that the use of the closest specimen to Kotaro Minami, the use of young athletes just to study him. To be honest, they can narrow the athletes down to those athletes with the closest psychological background like that of Kotaro but nope; they went with random athletes in this case. Guess that one is cheaper compared to narrowing it down to those athletes close to Kotaro's overall physical and mental structure.

Remember what I said about Professor Kuromatsu having a bigger role later in the series? Turns out I was right as he is the head of this plan! Based on his first test subject, it seems that it involves the use of the Flea Mutant to inject some weird liquid on someone's body and it seems that it can increase their adrenaline. Since the first test subject failed, the evil professor decides to look for another subject. This time, his latest subject is Kotaro's friend, Hayami who happens to be a racer.

Unlike other racers, he has trouble in the hairpin part of the race track, if he can overcome it, he can be the best racer around. Since Professor Kuromatsu is involved, he undergoes to the same process the first test subject had. To put it simply, he is injected with monster steroids that will help boost his performance in the race track. One thing I notice with Professor Kuromatsu is that he has a different hand when he performs a specific surgery on someone. Though he barely used it during the operation, I guess its only purpose is to create electricity for the machines to function and to make him look more of an evil scientist.

As expected, he overcome his trouble in the hairpin part of the race track and is gaining more fans as he continues to win every race he is in. Because of his success thanks to the monster steroids, just like every guy who is taking a certain addictive drug, he wants more of it and the evil Professor gives him a better drug, to be exact, a hormone that will further boost his speed in the race track. Instead of boosting his performance, it makes him worse as he becomes a coward in the race track after he is injected with the hormone. I didn't expect that he will have that kind of side effect, I was originally expecting that he will turn into a Mutant or something since hey, the next step after in taking monster steroids is to become a monster! ​

Much to my surprise, he ended up becoming a monster! It didn't help that the mutation scene is well done that it reminded me of a clip from an old black and white movie called "Metropolis" that I saw years ago. His mutation also made me remember some old book that features how to turn someone into a werewolf with the use of prosthetic makeup. Because of this mutation, he tried to look for answers via Professor Kuromatsu only to end up discovering that he is just a test subject for a hormone, which will be used against Kamen Rider BLACK.

Luckily, he escaped and Kotaro sees him. Instead of fighting Hayami, now a full-fledged werewolf with some of his consciousness left intact, he tries to comfort his friend. Heck, during the scene when he tries to run on a cliff to commit suicide, Kotaro decides to save him! This is when the Flea Mutant comes in and injects him the same hormone that turned Hayami into a coward. To be honest, I didn't see the effect of the hormone in Kotaro's body since the effect lasted for at least 2-5 seconds before he remembers what happened to his stepfather in the first episode. ​

Kamen Rider's fight with the Flea Mutant is interesting, unlike his previous fights with other Mutants, the Flea Mutant likes to jump around, making him an impossible target for Kamen Rider BLACK. Thankfully, he uses his Multi-Eye ability to see through his jumping ability and finally, defeat him at the very end. Back to Professor Kuromatsu, he is punished for failing, and I am fine with it because he just pick up random athletes for crying out loud and not further study their main target for him to create a Coward Hormone that can affect Kotaro's mentality. As for Hayami, he is back to normal and is now working hard for his dream to become the fastest man around in a motorcycle.